Little Moreau #1 dam
Little Moreau #1
Little Moreau #1 is a state-owned earth dam located in Dewey, South Dakota, along the picturesque Little Moreau River. Built in 1933 by the Works Progress Administration (WPA), this dam stands at a height of 30 feet and has a storage capacity of 507 acre-feet. With its uncontrolled spillway and low hazard potential, it serves as a vital water resource for the region, providing irrigation and flood control benefits to the surrounding area.
Managed by the South Dakota Department of Agriculture and Natural Resources, Little Moreau #1 is subject to regular state inspections and enforcement to ensure its structural integrity and compliance with regulations. Despite its moderate risk rating, the dam has not been assessed for its condition, emergency action plan preparedness, or risk management measures. With its historical significance and continued importance in water resource management, Little Moreau #1 remains a key piece of infrastructure in the region, contributing to the overall resilience of the local ecosystem and community.
As climate change continues to impact water resources and weather patterns, the role of dams like Little Moreau #1 becomes increasingly crucial in mitigating risks and adapting to changing conditions. With its strategic location and operational history, this dam stands as a testament to the enduring importance of water resource management in the face of evolving climate challenges.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Little Moreau #1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Moreau R Near Whitehorse Sd | 53 cfs | → |
| Grand R At Little Eagle Sd | 65 cfs | → |
| Oak Cr Near Wakpala Sd | 10 cfs | → |
| Cedar Creek Nr Raleigh | 17 cfs | → |
| Moreau R Near Faith Sd | 12 cfs | → |
| Cannonball River Nr Raleigh | 15 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Little Moreau #1.
Track Little Moreau #1 in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Little Moreau #1
Where does the data for Little Moreau #1 come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the Low hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Little Moreau #1.